Motherboard compatibility question

[Krekie]

Hi, I am trying to upgrade my PC and I just dont want to mess it up. I have Asus P7P55-M motherboard and I need to know if I can buy Nvidia GTX760 GPU. I currently have GT440. Also, will my 400W KME PSU be sufficient? Thanks for help and sorry if I posted into wrong thread.
PS: If new PSU is needed, which one will be the best? (meaning cable stuff) Also, I have KME MidiTower ATX CX-0762 400W case.

 

[Calvin7]

GTX 760:
Minimum of a 500 Watt power supply
(Minimum recommended power supply with +12 Volt current rating of 30 amps)
An available 6 pin PCI-E and 8 pin PCI-E power connector

EVGA 600 B
http://www.newegg.com/Product/Product.aspx?Item=N82E16817438014